For most of its history, psychiatry has treated the brain as a chemical soup, adjusting neurotransmitters and waiting weeks to see whether anything changed. Transcranial magnetic stimulation (TMS) represents a different idea: that mental illness lives in specific, dysfunctional circuits, and that those circuits can be targeted directly. Since the Food and Drug Administration (FDA) first cleared TMS for treatment-resistant depression in 2008, the field has moved from a fixed scalp measurement toward circuit-guided, individualized treatment. For clinicians and patients alike, understanding which circuits are being treated today, and which may be treated tomorrow, helps separate established care from promising science.
The workhorse target remains the left dorsolateral prefrontal cortex (DLPFC). The original FDA-cleared protocol delivered 10 Hz stimulation to this region, located roughly 5 cm in front of the motor cortex, daily for about six weeks; in the pivotal trial, response was 23.9 percent with active treatment versus 12.3 percent with sham. The rationale has since sharpened: the most effective spots within the DLPFC are those functionally “anticorrelated” with the subgenual anterior cingulate cortex (sgACC), a deep hub of negative mood that the magnetic field cannot reach directly. Three refinements built on this circuit have also earned FDA clearance: intermittent theta burst stimulation, which shortened a 37-minute session to about 3 minutes; the H1 “deep TMS” coil, which stimulates both sides of the prefrontal cortex more broadly; and Stanford Neuromodulation Therapy, which combines functional MRI-guided targeting with ten sessions a day over five days. In August 2026, a JAMA Psychiatry editorial highlighted randomized evidence that connectivity-based targeting outperformed scalp-based targeting, with response rates of 80 percent versus 60 percent.
Obsessive-compulsive disorder (OCD) uses an entirely different circuit. OCD is linked to overactivity in the cortico-striato-thalamo-cortical loop, particularly the medial prefrontal cortex and dorsal anterior cingulate cortex, regions that act as an “error alarm” stuck in the on position. The FDA cleared the H7 deep TMS coil for OCD in 2018 after a multicenter trial in which 38.1 percent of patients responded to 20 Hz stimulation of these midline regions, compared with 11.1 percent on sham; each session followed a personalized symptom-provocation exercise designed to activate the circuit before treating it. A figure-8-style double-cone coil was later cleared as substantially equivalent, although electric-field modeling shows it reaches far less of the cingulate target than the H7. A small randomized trial in September 2026 reported a 75 percent response after only 10 H7 sessions over two weeks, a result that needs replication but suggests shorter OCD courses may be possible.
The next generation of targets is already in clinical trials, and they map onto distinct disorders. The dorsomedial prefrontal cortex appears to be a target specifically for anxiety: in patients with depression and prominent anxiety, stimulating this site improved anxiety, whereas the classic sgACC-linked DLPFC site improved depressive and suicidal symptoms more. For post-traumatic stress disorder, high-frequency stimulation of the right DLPFC has the most data, but an August 2026 meta-analysis of 16 randomized trials found a large self-reported benefit with low-certainty evidence and substantial heterogeneity. In schizophrenia, low-frequency stimulation of the left temporoparietal cortex can reduce persistent auditory hallucinations, and in OCD, low-frequency stimulation of the supplementary motor area and orbitofrontal cortex shows promise, although results vary widely across studies. For bipolar depression, researchers are examining the ventrolateral prefrontal cortex and anterior insula, nodes that regulate the amygdala and that may address mood instability rather than low mood alone. Stimulant use disorders, especially methamphetamine use disorder, are also being studied with prefrontal theta burst protocols.
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None of these emerging targets has FDA clearance, and enthusiasm should be measured. Many trials are small, sham blinding is imperfect, and follow-up is short. Even so, the direction is clear. Psychiatry is moving from “one spot for everyone” toward matching a patient’s symptoms to a specific circuit, guided by imaging and electric-field modeling, and eventually perhaps reaching deep structures such as the amygdala with technologies like low-intensity focused ultrasound. For patients who have exhausted medications, that shift offers something that has long been missing: treatment aimed precisely at the circuits causing the symptoms.
Ravi Singareddy is the founder and medical director of Empower Psychiatry & Sleep in north metro Atlanta, where he leads an interventional psychiatry practice offering transcranial magnetic stimulation (TMS) and Spravato (esketamine) for treatment-resistant depression. Double board-certified in psychiatry and sleep medicine, he brings more than two decades of clinical and academic experience to patients who haven’t found relief with medications alone. He is affiliated with Emory Healthcare.
His interest in neuromodulation dates back to his years as associate professor of psychiatry at Penn State College of Medicine. There, he taught annually on vagus nerve stimulation and novel depression therapies, and he published on long-term combined electroconvulsive therapy and vagus nerve stimulation in the American Journal of Psychiatry. He has authored numerous peer-reviewed papers on sleep disorders, insomnia, anxiety, and depression, with work appearing in Sleep, the Journal of Clinical Sleep Medicine, and Psychiatry Research.
Singareddy is a Fellow of the American Psychiatric Association and the American Academy of Sleep Medicine and practices measurement-based care, tracking outcomes to guide every treatment decision. He shares updates on Instagram.
